According to the foregoing, the Google Map uses the web Mercator for China is to do a coordinate encryption processing, and there is no encryption abroad, so, has always been a question mark: How to deal with the edge? That is to say, what happens on the border, the following two experiments will illustrate the problem.
Experiment Two: Google Maps (street map) border issues
Dandong, Liaoning (Central-DPRK border)
Guangxi Dongxing (Sino-Vietnam border)
There is no doubt that the basic no processing, complete chaos, helpless.
Experiment Three: Google Map (image map) will be how to deal with the street can be wrong, the image will be?
Or in the dongxing of Guangxi (Sino-Vietnam border)
The imagery is normal, and the overlapping streets are chaotic.
Image Normal, it means that the image is not offset, this point we look at the East gate of Tsinghua Image Overlay Street.
Look carefully will find that the image of the Tsinghua East Gate School motto position and the previous article in the Google Map Mark location is basically overlapping. This is a good illustration of the image without any offsets, and the street map is encrypted.
In summary, Google's own street map and image map in China is not superimposed, while Google map of the Chinese border Street map is completely chaotic, but for the National Testing Bureau encryption requirements, Google very helpless.
Off-topic: So how does the high-German map behave?
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(Inside out) web map coordinate system--Google's frustration